The present invention relates to a process for preparing uni-core detergent particles being excellent in dissolubility and flowability properties, the uni-core detergent particles formulated with a powdery builder and supporting a surfactant composition.
General processes for preparing powdery detergent particle containing a powdery builder include a preparation process comprising dissolving or dispersing components which are desired to be formulated in water, and spray-drying the mixture; a preparation process comprising aggregating (granulating) a powdery builder with a liquid binder or by compression; a dry-blend process; an extrusion/disintegration process of a detergent component paste; or combinations of the above processes. However, in these preparation processes, it has been difficult to satisfy both the fast dissolubility and the flowability properties of the detergent particle.
Accordingly, an object of the present invention is to provide a process for preparing uni-core detergent particles being excellent in the dissolubility and the flowability properties in the process for preparing detergent particles comprising a powdery builder.
The above object and other objects of the present invention will be apparent from the following description.
Specifically, the present invention relates to:
[1] a process for preparing uni-core detergent particles having a degree of particle growth of 1.5 or less and a bulk density of 500 g/L or more, comprising the steps of:
(A-I): mixing base particles for supporting a surfactant which have an average particle size of from 150 to 500 xcexcm and a bulk density of 400 g/L or more [Component (a)] with a surfactant composition [Component (c)];
(A-II): mixing a mixture obtained in Step (A-I) with a powdery builder [Component (b)] of which primary average particle size is from 3 to 30 xcexcm in an amount of from 5 to 50 parts by weight, based on 100 parts by weight of Component (a); and
(A-III): mixing a mixture obtained in Step (A-II) with a fine powder [Component (d)] of which primary average particle size is smaller than that of Component (b) in an amount of from 5 to 100 parts by weight, based on 100 parts by weight of the mixture,
wherein a formulation ratio of Component (a) and Component (c) in Step (A-I) is such that an amount of Component (c) is from 20 to 100 parts by weight, based on 100 parts by weight of Component (a);
[2] a process for preparing uni-core detergent particles having a degree of particle growth of 1.5 or less and a bulk density of 500 g/L or more, comprising the steps of:
(B-I): mixing Component (a), a powdery builder [Component (bxe2x80x2)] of which primary average particle size is from 5 to 50 xcexcm and Component (c); and
(B-II): mixing a mixture obtained in Step (B-I) with a fine powder [Component (dxe2x80x2)] of which primary average particle size is smaller than that of Component (bxe2x80x2) in an amount of from 5 to 100 parts by weight, based on 100 parts by weight of the mixture,
wherein formulation ratios among Component (a), Component (bxe2x80x2) and Component (c) in Step (B-I) are such that an amount of Component (bxe2x80x2) is from 5 to 50 parts by weight and an amount of Component (c) is from 20 to 100 parts by weight, based on 100 parts by weight of Component (a), and wherein the primary average particle size of Component (dxe2x80x2) is smaller than that of Component (bxe2x80x2); and
[3] a process for preparing uni-core detergent particles having a degree of particle growth of 1.5 or less and a bulk density of 500 g/L or more, comprising the steps of:
(C-I): mixing Component (a), Component (bxe2x80x2) in an amount of from 5 to 50 parts by weight, based on 100 parts by weight of Component (a), and Component (c);
(C-II): mixing a mixture obtained in Step (C-I) with Component (b) in an amount of from 5 to 50 parts by weight, based on 100 parts by weight of Component (a); and
(C-III): mixing a mixture obtained in Step (C-II) with Component (d) in an amount of from 5 to 100 parts by weight, based on 100 parts by weight of the mixture,
wherein a formulation ratio of Component (a) and Component (c) in Step (C-I) is such that an amount of Component (c) is from 20 to 100 parts by weight, based on 100 parts by weight of Component (a).